ModulusChecking.Models.BankAccountDetails.BankAccountDetails C# (CSharp) Метод

        public BankAccountDetails(string sortCode, string accountNumber)
        {
            accountNumber = PrepareString(accountNumber);
            sortCode = PrepareString(sortCode);

            switch (accountNumber.Length)
            {
                case 9:
                    var chars = sortCode.ToCharArray();
                    chars[5] = accountNumber[0];
                    sortCode = new string(chars);
                    accountNumber = accountNumber.Substring(1);
                    break;
                case 10:
                    if (SortCode.IsCooperativeBankSortCode(sortCode))
                    {
                        accountNumber = accountNumber.Substring(0, 8);
                    }
                    else if (SortCode.IsNatWestSortCode(sortCode))
                    {
                        accountNumber = accountNumber.Substring(2);
                    } else
                    {
                        throw new ArgumentException(string.Format("Ten Digit Account Numbers can only come from Natwest or Coop sortcodes. {0} does not appear to be either",sortCode));
                    }
                    break;
            }

            SortCode = new SortCode(sortCode);
            AccountNumber = AccountNumber.Parse(accountNumber);
        }